Haemophilus influenzae
Overview
Haemophilus influenzae, formerly called Pfeiffer's bacillus or Bacillus influenzae, is a non-motile Gram-negative coccobacillus first described in 1892 by Richard Pfeiffer during an influenza pandemic. A member of the Pasteurellaceae family, it is generally aerobic, but can grow as a facultative anaerobe.[1] H. influenzae was mistakenly considered to be the cause of influenza until 1933, when the viral etiology of the flu became apparent. Still, H. influenzae is responsible for a wide range of clinical diseases.
Symptoms
* unusual irritability * difficulty sleeping or staying asleep * tugging or pulling at one or both ears * fever * fluid draining from ear(s) * loss of balance * hearing difficulties * ear pain * nausea and vomiting * diarrhea * decreased appetite * congestion
Causes
The H. influenzae bacteria live in the upper respiratory tract and are usually transmitted by close contact with an infected individual. Droplets in the air from a sneeze can be inhaled and may also cause infection.
Prevention
Immunization against type b, which is the most invasive strain of H. influenzae, is routinely administered in a three- or four-part series. The first vaccine is received at 2 months of age and the two subsequent doses are given at about 4 months and 6 months. A booster is then given between 12 and 15 months of age. If a child did not receive the vaccine and is older than 5 years, it may not be necessary for them to be immunized. Other populations that should be encouraged to receive the vaccine include the following: * adults and children with sickle cell disease * individuals without a spleen * adults and children with weakened immune systems * individuals who are HIV positive
Diagnosis
Clinical diagnosis of H. influenzae is typically performed by bacterial culture or latex particle agglutination. Diagnosis is considered confirmed when the organism is isolated from a sterile body site. In this respect, H. influenzae cultured from the nasopharyngeal cavity or sputum would not indicate H. influenzae disease because these sites are colonized in disease free individuals.[4] However H. influenzae isolated from cerebrospinal fluid or blood would indicate a H. influenzae infection.
Treatment
Treatment for H. influenzae greatly depends on which area of the body is infected. Specific treatment for H. influenzae will be determined by your child's physician based on: * your child's age, overall health, and medical history * extent of the disease * your child's tolerance for specific medications, procedures, or therapies * expectations for the course of the disease * your opinion or preference Regardless of the location, antibiotics may be used to treat infections caused by H. influenzae. The length of treatment varies depending on the location and severity of the infection. Other therapy will be supportive (aimed at treating the symptoms present).